In the decades since, the damage has lived on among those who were exposed. Washington, while admitting to and addressing these defoliants’ long-lasting effects in Vietnam––and continuing to account for the U.S.’s explosive Cambodian and Laotian legacy––has largely sidestepped the issue of dioxin in these two officiallyneutral neighboring nations, maintaining that the chemicals were not widespread there, despite records indicating otherwise. Accordingly, the U.S. offers no assistance to affected Cambodians and Laotians, and constrains benefits to Americans who secretly served in those countries without entering Vietnam but still may have been exposed.

Such denialism contrasts with the notion that the U.S., in pursuing military intervention, assumes at least some responsibility for the post-conflict well-being of those affected. American shirking of such responsibility—a marked divergence from the country’s famed post–World War II efforts—has become common, such as in Libya, Iraq, and Afghanistan. In the case of the Vietnam War, the U.S. used a borderless weapon, yet has since used national borders to leave those exposed to dioxin to suffer without support.

In 1991, Congress passed a law promising benefits for 2.4 million dioxin-affected American veterans, and the Department of Veterans Affairs has since presumed that all who served in Vietnam were exposed and are entitled to assistance. But this does not wholly account for dioxin’s genetic loitering, as the VA makes payments to descendants of exposed veterans only when they have spina bifida or are the children of a small number of female veterans with 18 other diseases. The VA withholds these benefits from those with all other likely dioxin-caused defects, which, according to ProPublica, “leaves out the vast majority of vets’ ailing children.”